What does a cammed v8 mean?

“Camming”, or replacement of the engine’s camshaft(s), helps the engine make more power by altering valve lift, timing, and duration. Certain camshaft profiles help the engine breathe better at certain RPM ranges, usually up high in the case of a performance cam.

What RPM big cam idle?

It’s not easy to get a big cam to idle smoothly at 650 RPM (but it may be possible), so you want to go for something easy first. For example, if you have a cam that’s between stock size and 224 degrees intake duration, try an initial target idle speed of 800 RPM.

Are cammed cars reliable?

A cammed car is perfectly reliable and you don’t have a hair on your nut sack if you don’t cam that car.

What time should you idle?

Usually timing is at 5 degrees before top dead center, but sometimes there will be a vacuum diaphragm to retard the timing at idle for emissions control purposes.

What is good idle vacuum?

Idle vacuum for most engines is about 18 to 22 in. If vacuum is steady at idle but lower than normal, the ignition or valve timing may be retarded. Low compression, an intake leak or tight valves also can cause low vacuum at idle.

What kind of car is a cammed V8?

“Cammed” cars replace the cams with one’s designed exclusively to run well at high rpms and high throttle application.

What kind of idle does a cross plane V8 have?

“Lopey” idle from a cross plane V8 is exascerbated by lumpy cams. Good page here showing how how the consecutive firing of 3&5 and 4&6 of each bank creates a larger equivalent exhaust pulse (unless using equal length headers) http://www.projectm71.com/Cross_FlatPlane.htm Here’s a good article about camshafts.

What makes a car have a big cam?

Valve overlap. The exhaust and intake valves are open at the same time which causes a choppy idle. Calling it a ‘big cam’ generally refers to the lift of thr cam. High performance cams also often have more valve overlap because they have longer duration, keeping the valves open longer.

What happens when you run a big cam at low rpm?

Running a big cam at low rpm actually gets insufficient air/fuel (well, sub-optimal, but you get the picture) into the engine. In addition, you’d normally think the intake valve opens right at top dead center, what you’d traditionally consider the end of the exhaust stroke and beginning of the intake stroke.